The invention relates to improvements in plier-shaped tools in general, and more particularly to improvements in multiple-purpose plier-shaped tools. Still more particularly, the invention relates to improvements in multiple-purpose tools which can be used with advantage for the shaping and severing or trimming of strip-shaped and/or wire-like products (hereinafter called wires for short).
U.S. Pat. No. 4,337,542 to Theier discloses a terminal crimping tool which can be utilized for manipulation of electrical connectors and terminals. The patented tool can be used as a means for stripping insulating sheaths off wire-like conductors having different diameters as well as to sever wire-like conductors. In addition, the patented tool can be used to crimp end portions of wire-like conductors and/or to form eyelets of different diameters. One lever of the tool is provided with a transversely extending groove which is parallel to the axis of the pivot member for the two levers, and the other lever has a transversely extending projection which can enter, with a certain amount of clearance, the groove in response to pivoting of the jaws of the two levers toward each other. The projection cooperates with the surface which surrounds the groove in order to shape a selected portion of an electric conductor.
A somewhat similar multiple-purpose tool is disclosed in U.S. Pat. No. 4,104,752 to Amrein et al. The two halves or levers of the tool are pivotally connected to each other and are provided with complementary insulation-stripping portions as well as with cutting edges for pieces of wire or the like. Still further, the two halves of the patented tool are provided with reaming devices as well as with complementary contouring portions. The tool of Amrein et al. also comprises a projection which extends in parallelism with the pivot axis, and a complementary groove which can receive the projection with a certain amount of clearance.
A drawback of presently known multiple-purpose tools is their lack of versatility and inability to carry out certain types of work. By way of example, orthodontists and makers of dental prostheses must shape different types of wire in a number of specific ways in order to impart to the wire a configuration which is needed in a brace or in another mechanical aid. These specialists are compelled to operate with a variety of different plier-shaped tools in order to carry out a series of successive operations upon a particular length of wire. As a rule, an orthodontist or a maker of dental prostheses will utilize at least three discrete types of plier-shaped tools, namely side nippers (which are used exclusively to sever pieces of wire), holding tools and shaping or forming tools. A holding tool serves to grasp a piece of wire in order to facilitate and simplify a bending or a like operation, for example, around a conical or cylindrical jaw of the holding tool. A shaping or forming tool is designed to engage a piece of wire at more than two discrete points and to impart to the wire a corrugated, zig-zag or like configuration as a result of movement of the jaws toward each other.
It will be seen that, at least in the field of orthodontics and dental prosthetics, there exists an urgent need for a tool which can perform a number of different operations in any desired sequence in order to save time as well as to avoid repeated switching from one tool to another.